public class Rotation extends TransformationGeometrique {

  public Rotation() {
    super();
  }

  public Rotation(float x,float y,float z,float a) throws ArithmeticException {
    super();
    calcul(x,y,z,a);
  }

  public Rotation(Direction d,float a) throws ArithmeticException {
    super();
    calcul(d.c[0],d.c[1],d.c[2],a);
  }

  public void calcul(float x,float y,float z,float a) throws ArithmeticException {
    float d =(float) Math.sqrt(x*x+y*y+z*z);
    x /= d;
    y /= d;
    z /= d;
    float c =(float) Math.cos(a);
    float s =(float) Math.sin(a);
    m[0][0] = x*x+c*(1.0F-x*x);
    m[0][1] = x*y*(1.0F-c)-z*s;
    m[0][2] = x*z*(1.0F-c)+y*s;
    m[1][0] = x*y*(1.0F-c)+z*s;
    m[1][1] = y*y+c*(1.0F-y*y);
    m[1][2] = y*z*(1.0F-c)-x*s;
    m[2][0] = x*z*(1.0F-c)-y*s;
    m[2][1] = y*z*(1.0F-c)+x*s;
    m[2][2] = z*z+c*(1.0F-z*z);
  }
}